On 07/05/11 11:04, Martin Rowley wrote:

....


07/0558Z - 07/0630Z (latter time determined by the 10-minute rule):
weak, low audio-frequency rumbles fairly near, with short period of
moderate/heavy rain around the start of the period, soon becoming
slight.

Martin, what's the 10-minute rule?

Total rainfall in rain-day ending 07/0900Z = 11.2 mm which represents
roughly a fifth of our eLTA 1971-2000, useful, but already evaporating
readily despite the rather high dew points (13degC).

Almost identical to here. It was probably the same cloud system passing by.

Repeat performance possible this evening I fancy ....

I'm sure you're right. It looks like something rather longer, though
perhaps intermittent.

Hugh